Field of the Invention
One or more exemplary embodiments of the present invention relate to an apparatus and method for measuring a pretilt angle of a liquid crystal (LC).
Description of the Related Art
An LC cell used in liquid crystal display (LCD) devices generally includes a lower substrate, an upper substrate facing the lower substrate, and an LC layer between the lower substrate and the upper substrate.
As the lower substrate is a display substrate, a plurality of data lines and a plurality of gate lines, which define a plurality of pixel regions, are arranged on the lower substrate, switching elements, such as a thin-film transistor, are arranged in regions where the plurality of data lines and the plurality of gate lines cross each other, and pixel electrodes are located in pixel regions. A color filter may be disposed, for example, under the upper substrate.
To improve the display performance of an LCD device, LC molecules are initially oriented to make a predetermined angle with a substrate surface. The initial orientation angle of an LC molecule is referred to as a pretilt angle.
Since the display performance of the LCD device depends on the pretilt angles, the pretilt angles need to be detected.